Art of producing sound films



P 1942- H. WESTERKAMP' 7 2,297,517

ART OF PRODUCING SOUND FILMS Filed Aug. 6, 1940 i-FT y In venfor:

Patented Sept. 29, 1942 ART OF PRQDUCING SOUND IFS Hugo Westerkamp,Cologne-Braunsfeld, (Sier-v many; vested in the Alien Property CustodianApplication August 6, 1940, Serial No. 351,560 1111 Germany September26, 1939 to the recorded surface of the wax ribbon until.-

the layers formed in this way, whenhardcned, have the thickness of thedesired matrix, whereupon the ribbon-shaped layer is withdrawn from thewax ribbon. In doing this, it must be observed thateach thin layer ofthe substance forming the matrix is dry before the next layer isapplied.

It is advisable to add to the matrix substance tanning materials ofknown composition (metal chrome compounds, such as for example sodiumbichromate). It is also possible to spray hardening materials of knowntypes (formaldehyde or the like) on the surface of the matrix while thematrix substance is drying.

In practice, this method may be performed in various ways, for exampleby first helical winding up the original wax ribbon, then dippi thewound up wax ribbon into a bath of the matrix substance whilesimultaneously rotating about the axis of the helix, drying the layer,repeating this dipping operation after each layer formed on the waxribbon has dried, until the film of the matrix substance has acquiredthe thickness or" the matrix ribbon, and finally withdrawing the film ofthe matrix substance from its base.

iii)

- cally termed a gelatin material.

Another way of proceeding consists in continuously applying the matrixsubstance in a thin layer to the surface of the original wax ribbon bymeans of a roller partly dipping into the bath. and arranged oppositethe original wax ribbon, whereupon the hardened film of the matrixsubstance formed on the wax ribbon, after having acquired the desiredthickness, is withdrawn from. the wax ribbon.

A third way of proceeding is to apply the matrix substance by means of aslotted nozzle onto the recorded surface of the original recordingribbon moved past the opening in the nozzle, and then withdrawing thelayer of the matrix substance thus formed on the wax ribbon, after ithas hardened, from the wax ribbon.

With the two last mentioned methods the devices known to experts willserve the purpose; however, in practising the first mentioned procedureit is advisable to use a special kind of device in which there isarranged, above a container for the liquid or liquefied matrixsubstance, a helical ribbon carrier mounted to rotate 8 Claims. (Cl.18.5)

about a horizontal axis and adjustable in vertical direction so that bylowering it. the helical surface partly dips into the bath of the matrixsubstance.

With the procedure described a novel type of matrix is formed forproducing a series of duplicate sound films having mechanical soundrecords, which difiers from known types of similar matrices inasmuch asit consists of a plurality of layers of a gelatinous substance, such asgelatine or gelatinated albumin, hereinafter generi- Threeconstructional forms of devices for performing the method describedabove are diagrammatically illustrated on the accompanying drawing, inwhich:

Figure l is a diagrammatic showing of appa-' ratus by which theinvention may be practiced.

Figure 2 is a view of another form of apparatus for practicing theinvention.

Figure 3 is a cross-sectional view indicating a third form of apparatus.

In the constructional form shown in Fig. l, a container 9 receives theliquidor liquefied matrix substance, for example liquefied gelatine 2.Above the container with the matrix substance, a roller 3 for applyingthe substance is rotatably mounted so as to partly dip into the bath ofthe substance 2; of course, it is necessary to maintain the level of theliquid in the container 5 at such a height that the depth of immersionof the roller 3 remains approximately constant.

Above the roller 3 there is a counter roller 3 mounted to rotate at adistance sumcient to let the original wax ribbon, from which the matrixis to be made, pass between the rollers. The original wax ribbon 5 isdrawn, as shown, over the roller ti and between the rollers 3 and 4.

The rollers rotate in the same angular direction and preferably atdifferent speeds with respect to each other, the dipping roller 3 havinga stripper M which serves to regulate the quantity of substance carriedto the surface of the running wax ribbon. The dipping roller 3 transfersthe layer of substance carried by it to the surface of the wax ribbon,the liquid substance moving wax ribbon 5, it may be assured that theportions of the wax ribbon, to which a thin layer of the matrixsubstance has been applied, are dry when they return to the place wherethe substance is applied. Finally, the ribbon-like film of materialapplied to the wax ribbon is withdrawn from the latter; it forms thematrix which is excellently suitable for the production of a series ofduplicate sound film' copies. The sound film copies may, for example, beproduced by pressing the matrix on blank sound film strips, butpreferably the copies are produced by a casting process corresponding tothat in Fig. 3 and utilizing an appropriate material for the dupli--cate record.

In the constructional form shown in Fig. 2, a helically coiled ribbonconsisting of any resisting material of approximately the same width asthe original wax ribbon is disposed so as to have a uniform distancefrom the axis of the turnin shaft and to be rotated with the turningshaft.

comprises repeatedly applying thin layers of a mixture of a liquidgelatine material and a gelatine hardening agent to the surface of thewax ribbon and hardening and drying each individual layer prior to theapplication of the succeeding layer, said repeated application. anddrying being continued until the desired thickness has been established,and withdrawing the ribbon-like.

film from the wax ribbon as a matrix for producing duplicate copies.

3. A method for producing a duplicate matrix 7 from a wax ribbon havinga mechanical sound record upon the surface thereof, which comprisesrepeatedly applying thin layers of a liquid gelatine material to thesurface of the wax ribbon,

. applying a hardening agent to each layer of the As shown in theillustration, a kind of inter-' rupted cylindrical carrier is formedwith spaced convolutions, on whose helical path the original wax ribbonis p aced with the recorded side towards the axis of the helix and isthus also wound up helically. The carrier 9 is arranged so that ofmatrix substance is applied to the recorded surface of the wax ribbon.Thereupcn the carrier is raised for a time sufficient to let the matrixsubstance dry, and a'known kind of hardening material, such asformaldehyde or the like, from the pressure vessel ll may be blown fromthe apertured tube I2 on to the surface of the layer formed. Then, thecarrying body is lowered again and rotated the procedure described beingrepeated until the substance applied to the wax ribbon has acquired thedesired thickness. Finally, the film of applied substance is withdrawnfrom the wax ribbon and constitutes the finished matrix.

In Fig. 3, the container Ia holds a bath of gelatinous substance inliquid condition. An opening is provided at the lower side of thecontainer leading to a slotted nozzle 13. The wax ribbon 5, having themechanical sound record on its upper surface, is led over a guide l4, sothat the thin layer of liquid gelatine formed by the nozzle l 3 isdeposited from the container la upon the recorded surface of the waxribbon to provide a layer l5. This layer I5 is then dried, and thedepositing of a thin layer can then be repeated a desired number oftimes, alternating with drying, until the film has been built up to thedesired thickness for the matrix.

'What is claimedis:

l. A method for producing a duplicating matrix from a wax ribbon havinga mechanical sound record upon the surface thereof, which comprisesrepeatedly applying thin layers of a liquid gelatine material to thesurface of the wax ribbon and effecting a hardening of each individuallayer by the action of the hardening agent and the substantiallycomplete drying thereof prior to the application of the succeedinglayer, said repeated application and drying being continued until thedesired thickness has been established, and withdrawing the ribbon-likefilm from gelatine material and drying the same prior to the applicationof the succeeding layer, said applications of gelatine material andhardening agent and said drying being continued until the desiredthickness has been established, and withdrawing the ribbon-like film.from the wax ribbon as a matrix for producing duplicate copies.

4. A method for producing a duplicating matrix from a wax ribbon havinga mechanical sound record upon the surface thereof, which comprisessupporting the wax ribbon as a helical coil, dipping a portion of eachconvolution of the coil into a bath .of liquid gelatine material androtating the coil about its axis to effect successive deposit of a thinlayerof the material for the length of the waxribbon, effectinghardening of the material after the deposit by the action of thehardening agent and drying the same, repeating the successive depositionand drying until a film of the desired thickness has been established,and withdrawing the ribbon-like film from the wax ribbon as a matrix forproducing duplicate copies.

5. A method for producing a duplicating matrix from a wax ribbon havinga mechanical sound record upon the surface thereof, which comprisessupporting the wax ribbon as a helical coil with the recorded surfacedirected toward the axis, clipping a portion of each convolution of thecoil .into a bath of liquid gelatine material and rotating the coilabout its axis to'effect successive de-' posit of a thin layer of thematerial for the length of the wax ribbon, applying a hardening agentand drying the material after the deposit, repeating the successivedeposition and application of hardening agent and drying until a film ofthe desired thickness has been established, and withdrawing theribbon-like film from the wax ribbon as a matrix for producing duplicatecopies.

6. A method for producing a duplicating matrix I from a wax ribbonhaving a mechanical sound record upon the surface thereof, whichcomprises supporting the wax ribbon as a helical coil, dipping a portionof each convolution of the coil into a bath of liquid gelatine materialand rotating the coil about its axis to effect successive deposit of athin layer of the material upon a length of the wax ribbon, blowing agelatine hardening material. upon portions of said convolutions.

which are out of the bath and drying the material, repeating thesuccessive deposition, hardening and drying operations until 'a film ofthe desired thickness has been established, and withdrawing theribbon-like film from the wax ribbon as a matrix for producing duplicatecopies.

7. A method for producing a duplicating matrix from a wax ribbon havinga mechanical sound record upon the surface thereof, which comprisespreparing a thin layer of gelatine material, bringing the recordedsurface of the wax ribbon into contact with said thin layer and therebydepositing the layer upon the wax ribbon, hardening the layer ofmaterial by the action or the 10 hardening agent anddrying the same,repeating the successive deposition and hardening until a wax ribbon asa matrix for producing duplicate 15 copies.

8. An apparatus for producing a duplicating matrix from a wax ribbonhaving a mechanical sound record upon the surface-thereof, comprising acontainer for a bath of liquid gelatine material, a support for said waxribbon comprising a carrier of helical form, means for presenting aportion of each convolution oi the wax ribbon on said carrier in thebath and for rotating the wax ribbon about the helical axis to eirectsuccessive deposit of a thinlayer of the material upon the length of thewax ribbon, and meanstor blowing HUGO WESTERKAMP.

